As Members of Congress--and as Americans--we are united in our unequivocal commitment to prevent Iran from obtaining a nuclear weapon. The proliferation of nuclear weapons in the Middle East would threaten the security of the United States and our allies in the region, particularly Israel.

The ongoing implementation of the Joint Plan of Action agreed to by Iran and the "P5+1" nations last November increases the possibility of a comprehensive and verifiable international agreement. We understand that there is no assurance of success and that, if talks break down or Iran reneges on pledges it made in the interim agreement, Congress may be compelled to act as it has in the past by enacting additional sanctions legislation. At present, however, we believe that Congress must give diplomacy a chance. A bill or resolution that risks fracturing our international coalition or, worse yet, undermining our credibility in future negotiations and jeopardizing hard-won progress toward a verifiable final agreement, must be avoided.

We remain wary of the Iranian regime. But we believe that robust diplomacy remains our best possible strategic option, and we commend you and your designees for the developments in Geneva. Should negotiations fail or falter, nothing precludes a change in strategy. But we must not imperil the possibility of a diplomatic success before we even have a chance to pursue it.